From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jaehoon Chung Subject: Re: [PATCH] dw_mmc: support send_auto_stop Date: Thu, 31 Mar 2011 10:29:26 +0900 Message-ID: <4D93D8F6.7000904@samsung.com> References: <4D92C5D2.2000004@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7BIT Return-path: Received: from mailout3.samsung.com ([203.254.224.33]:32189 "EHLO mailout3.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754082Ab1CaBax (ORCPT ); Wed, 30 Mar 2011 21:30:53 -0400 Received: from epmmp2 (mailout3.samsung.com [203.254.224.33]) by mailout3.samsung.com (Oracle Communications Messaging Exchange Server 7u4-19.01 64bit (built Sep 7 2010)) with ESMTP id <0LIW00G54EVEST80@mailout3.samsung.com> for linux-mmc@vger.kernel.org; Thu, 31 Mar 2011 10:30:50 +0900 (KST) Received: from TNRNDGASPAPP1.tn.corp.samsungelectronics.net ([165.213.149.150]) by mmp2.samsung.com (iPlanet Messaging Server 5.2 Patch 2 (built Jul 14 2004)) with ESMTPA id <0LIW005MEEV4PO@mmp2.samsung.com> for linux-mmc@vger.kernel.org; Thu, 31 Mar 2011 10:30:40 +0900 (KST) In-reply-to: Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Will Newton Cc: Jaehoon Chung , "linux-mmc@vger.kernel.org" , Chris Ball , Kyungmin Park Will Newton wrote: > On Wed, Mar 30, 2011 at 6:55 AM, Jaehoon Chung wrote: >> This patch is set the send_auto_stop bit in CMD register. >> If use DW_MCI_QUIRK_SEND_AUTO_STOP, helps to send an exact >> number of data bytes. >> >> >> Signed-off-by: Jaehoon Chung >> Signed-off-by: Kyungmin Park > > This is something I have been meaning to look into, does it improve > latency or throughput in your experiments? Not improve latency...but in my experiments, when i used this, i could find the stable throughput.. > > Is there a reason you have implemented it as a quirk? I would have > thought if it was a win (in performance or code size) it would be > applicable to all instances of this block? I didn't test every case..so Somebody doesn't want to use send_auto_stop, So i think good that used the quirks... you can see Send_Auto_Stop generation table in DesigneWare MMC controller spec I think that our case can use send_auto_stop...but i didn't ensure in other case > > If we implemented it as an unconditional feature then we could > probably remove some of the explicit stop handling code. > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >